Anchor bolts are widely used for the purpose of fastening machinery, process equipment, storage vessels, lamp posts, railings, columns, and other such items to suitable foundations, such as poured concrete. Installation of anchor bolts is commonly practiced by suspending them in position from a frame or template supported at about the level of the foundation to be poured and holding them in this position during the pouring and curing of the concrete. In this operation the anchor bolts are affixed to the template with their threaded ends extending upwardly through properly positioned holes in the template, a nut and, if necessary, a washer effecting the attachment.
While workable, the foregoing method of attachment leaves much to be desired. In the first place since it is not uncommon to have two to three inches of threads exposed above the top of the nut, a fair amount of time and effort is necessarily expended in applying and, subsequently, in removing the nut. In addition, in the pouring and distribution of the concrete, wet concrete is frequently splashed on the exposed threads. Compounding this problem is the ever-present tendency for the exposed threads to become rusty, especially in open-air installations. When these things happen it is often necessary to clean the exposed threads with a wire brush in order to back off the nut. Further, the exposed threads are susceptible to damage if accidently struck by objects being moved on or over the cured foundation prior to removal of the nut and the template.
In my U.S. Pat. No. 3,854,371 I have described an anchor bolt protective cap which overcomes the foregoing difficulties.
In order to permit adjustment of the position of the anchor bolt relative to the hardened concrete so that the bolt may be placed in proper registry with the cooperating holes in the base of the object to be fastened, it has been proposed heretofore to use anchor bolt sleeves or shields which furnish a void space around the shank of the anchor bolt. U.S. Pat. Nos. 3,430,408 and 3,500,607 are illustrative of such devices.
Published Netherlands patent application No. 6,809,623 describes a device for the removable connection of an anchor bolt and a form. A sleeve and a protective fastening part are employed.